Merge pull request #31 from vaz-ar/master

Updated the makefile to build without CGO

Makefile

@@ -1,9 +1,9 @@
 ifndef MAKE_DEBUG
-    MAKEFLAGS += -s
+	MAKEFLAGS += -s
 endif
 
-GO    := go
-PROMU ?= $(GOPATH)/bin/promu
+# Setting CGO_ENABLED to 0 disables CGO (cf. https://pkg.go.dev/cmd/cgo)
+CGO_ENABLED := 0
 
 GIT_TAG ?= $(shell git describe --tags --exact-match 2>/dev/null || echo "unknown")
 
@@ -13,20 +13,20 @@ PROJECT_OWNER ?= warmans
 PROJECT_NAME ?= aggregate-exporter
 DOCKER_NAME ?= $(PROJECT_OWNER)/$(PROJECT_NAME)
 
-LOCAL_BIN:="$(shell dirname $(realpath $(firstword $(MAKEFILE_LIST))))/.env/bin"
+LOCAL_BIN := "$(shell dirname $(realpath $(firstword $(MAKEFILE_LIST))))/.env/bin"
 
 .PHONY: install.linter
 install.linter:
 	curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(LOCAL_BIN) v1.51.2
 
-.PHONT: lint.go
+.PHONY: lint.go
 lint:
 	$(LOCAL_BIN)/golangci-lint run
 
 .PHONY: build
 build:
 	echo ">> building linux binary"
-	go build -o ${BIN_DIR}/prometheus-aggregate-exporter -ldflags "-X main.Version=${GIT_TAG}" ./cmd
+	CGO_ENABLED=$(CGO_ENABLED) go build -o ${BIN_DIR}/prometheus-aggregate-exporter -ldflags "-X main.Version=${GIT_TAG}" ./cmd
 
 .PHONY: build-arch
 build-arch:
@@ -37,7 +37,8 @@ ifndef GOARCH
 	echo "GOARCH must be defined"; exit 1;
 endif
 	echo ">> building $(GOOS) $(GOARCH) binary"
-	env GOOS=$(GOOS) GOARCH=$(GOARCH) go build -o ${BIN_DIR}/prometheus-aggregate-exporter-$(GOOS)-$(GOARCH) -ldflags "-X main.Version=${GIT_TAG}" ./cmd
+	GOOS=$(GOOS) GOARCH=$(GOARCH) CGO_ENABLED=$(CGO_ENABLED) go build -o ${BIN_DIR}/prometheus-aggregate-exporter-$(GOOS)-$(GOARCH) -ldflags "-X main.Version=${GIT_TAG}" ./cmd
+
 
 # Manual Testing
 #----------------------------------------------------------------------

README.md

@@ -39,20 +39,31 @@ the aggregate view.
     	
   -version (VERSION)
     	Show version and exit
-
 ```
+
 ### How to build it
 
 #### Build using the go binary
 
 If you have go (1.14) installed on your machine, you can simply do:
 
-    cd cmd/
-    go build -o prometheus-aggregate-exporter
+```shell
+cd cmd/
+go build -o prometheus-aggregate-exporter
+```
+
+To build without CGO enabled, which removes the dependency on `libc`, do:
+
+```shell
+cd cmd/
+CGO_ENABLED=0 go build -o prometheus-aggregate-exporter
+```
 
 Or you can use the provided Makefile:
 
-    make build
+```shell
+make build
+```
 
 #### Build into a Docker image
 
@@ -70,18 +81,19 @@ You can run the exporter against some static fixture files by running the follow
 in separate terminals.
 
 ```shell
-$ make test.run-fixture-server
-$ make test.run
+make test.run-fixture-server
+make test.run
 ```
 
 then to view the `/metrics` page:
 
 ```shell
-$ make test.scrape
+make test.fetch
 ```
 
 ### Example Usage
-```
+
+```shell
 ./bin/prometheus-aggregate-exporter \
 	-targets="http://localhost:3000/histogram.txt,http://localhost:3000/histogram-2.txt" \
 	-server.bind=":8080"
@@ -90,15 +102,15 @@ $ make test.scrape
 or using environment variables instead of flags: 
 
 
-```
+```shell
 TARGETS="http://localhost:3000/histogram.txt,http://localhost:3000/histogram-2.txt" \
 SERVER_BIND=":8080" \
 ./bin/prometheus-aggregate-exporter 
 ```
 
 or with docker
 
-```
+```shell
 docker run -it -p 8080:8080 -e TARGETS="http://localhost:3000/metrics" warmans/aggregate-exporter:latest
 ```